The present invention relates to purification of drinking water, and particularly to a device for purifying drinking water immediately prior to consumption by an individual.
With the increase of population of the world, together with increasing development of new chemical compounds and disposal of industrial waste over many years, increasing amounts of contamination are found in even the cleanest sources of available surface water and in well water. Adequate purification is not provided for publicly available drinking water in many areas of the world, and travelers not accustomed to the particular water supply in an area being visited often are made ill by contamination present in the water, although local residents are not noticeably affected. Additionally, dissolved gases and minerals present in the water may cause unpleasant taste or odor in the water, even though the water is safe for drinking. Furthermore, medical science is learning that many compounds often found in drinking water supplies may, over long periods of time, be carcinogenic.
As a response, water filtration devices have become available for incorporation in individual household water supply systems to purify drinking water. However, when water from other sources must be consumed, as in restaurants or when a person is traveling and filtered water supply sources are not readily available, it has previously not been convenient to obtain adequately purified drinking water, nor to purify the water which is available.
Gartner U.S. Pat. No. 4,298,475 discloses a portable water purifier including a filter including mechanical filtration elements, bactericidal agents, and an adsorbent material contained within the tubular filter housing so that a user may supply suction from the mouth to draw water through the tube to filter out foreign material and purify the water prior to use. Gartner makes no provision, however, for retention of water within the filter medium for any particular length of time as may be necessary for adsorption of contaminating materials from a quantity of water, with the resultant likelihood of inefficient purification of water by the device disclosed in that prior patent.
Gartner U.S. Pat. No. 4,420,590 discloses certain resins useful as filter media for treatment of drinking water.
Athletes, in particular, often require relatively large quantities of water for consumption during athletic exercise, as, for instance, during long foot races, bicycle races, soccer games, and hiking. Recently, plastic squeeze bottles with drinking tubes extending through removable caps have become popular, particularly for use by athletes, who carry the bottles full of water o other electrolyte-replacement liquids for consumption during the course of athletic events. Such bottles are convenient, for example, for bicyclers, who can carry them clipped to the frame of the bicycle, or for track and swimming competitors, who have their preferred liquids available in such bottles to be drunk between heats. However, such bottles contain a limited amount of water brought from an available source of water of satisfactory purity, and once consumed, such water must be replaced by whatever water is available, which may not always be acceptably pure.
What is needed, therefore, is a way to purify locally available water to provide drinking water which is acceptably pure and free from objectionable odors and tastes, as well as being acceptably free of microbial organisms which might cause illness. Preferably such a water purification device should be easily portable, and should be convenient for use in places such as restaurants, so that travelers will not jeopardize their health by being embarrassed to use such a device in a restaurant.